Ecology & Zoology

As climate change accelerates ice melt in the Arctic, polar bears may find caribou and snow geese replacing seals as an important food source, shows a recent study.

The research, by Linda Gormezano and Robert Rockwell at the American Museum of Natural History, is based on new computations incorporating caloric energy from terrestrial food sources and indicates that the bears' extended stays on land may not be as grim as previously suggested.

Examination of fossil fragments from Panama has led Smithsonian scientists and colleagues to the discovery of a new genus and species of river dolphin that has been long extinct. The team named it Isthminia panamensis. The specimen not only revealed a new species to science, but also shed new light onto the evolution of today's freshwater river dolphin species.

In the attempt to choose a mate, it's no surprise that females will select the more "attractive" of two males, but now a new study reveals that female túngara frogs are susceptible to the "decoy" effect, where the introduction of a third, inferior mate results in the female choosing the less attractive of the first two options.

The results of this study counter the rational choice models that are currently used in sexual selection theory, suggesting they may prove inadequate to explain decisions in socially complex and dynamic mating arenas.

To detect the occurrence of the decoy effect in frogs' mating choices, Amanda Lea and Mike Ryan conducted experiments using 80 female túngaras, which are known to be attracted to male calls of low frequency and long duration.

In a dramatic 2013 cover story, Time warned of “A World Without Bees,” subtitled “The price we’ll pay if we don’t figure out what’s killing the honeybee.” Its author argued that the class of agricultural pesticides know as neonicotinoids was killing the honeybee and that the planet would starve unless we banned these chemicals immediately. He said this because “1 in every 3 mouthfuls you’ll eat today,” depends on bee pollination. In short: no bees, no food.

If an unidentified flying object suddenly appeared in the sky, it's likely your heart would beat faster.

Now, researchers have found that the same is true for bears.

The UFOs in this case are actually unmanned aerial vehicles (UAVs), which have become increasingly valuable to wildlife researchers, allowing them to observe animals, including endangered species, in their natural settings from long distances and over difficult terrain. It had appeared as though the animals were taking these encounters in stride. For instance, American black bears rarely seem to startle or run away when a UAV comes near. But the new study reveals that despite the bears' calm demeanor when in the presence of UAVs, their heart rates soar, a sign of acute stress.

For more than a century, researchers have tried to pin down exactly why so many animal species play in their infancy. Now a new study in wild macaque monkeys has found that infants who play more actually boost key motor skills. However, these skills are acquired at a cost. The researchers also discovered that active infants grow more slowly.

So what are the evolutionary reasons behind this trade-off? And should human parents who want tall children sit them in front of the TV rather than letting them play in the garden?

Will the planet starve if bees disappear? Aren’t bees responsible for a significant chunk of the world’s food supply and nutrition, from one third to as much as 90 percent, depending on what advocacy group is making the claim? You hear such assertions invoked by advocacy groups, reported as truth by journalists and cited by politicians as accepted wisdom whenever the subject of pollinators comes up.

When it comes to vaccinating their babies, bees don't have a choice -- they naturally immunize their offspring against specific diseases found in their environments. And now for the first time, scientists have discovered how they do it.

Researchers from Arizona State University, University of Helsinki, University of Jyväskylä and Norwegian University of Life Sciences made the discovery after studying a bee blood protein called vitellogenin. The scientists found that this protein plays a critical, but previously unknown role in providing bee babies protection against disease.

People associate wasps with memories of picnic invasions, BBQs under siege, and painful stings. There is a lot more to these much-maligned insects though, and with more than 100,000 different species, their life histories range from the quietly unobtrusive to the bizarre and gruesome. A new study in the Journal of Experimental Biology documents one such disturbing example of wasp larvae that takes control of their unfortunate spider hosts.

The odds of being attacked and castrated by a variety of parasitic flatworms increases for marine horn snails the farther they are found from the tropics. A Smithsonian-led research team discovered this exception to an otherwise globally observed pattern--usually biodiversity is greatest in the tropics and decreases toward the poles.

The study makes a case for using host-parasite relationships as a tool to understand why there are typically more species--and more interactions between species--in the tropics than anywhere else in the world.